Keeping track of a control's transformation?

[Doug Lerner]

In a client application I am working on, I am drawing arrows and sending the
arrow information to a server, to be mirrored in other clients.

One thing that doesn't mirror perfectly though is this: in the client, when
you select and resize an arrow, you can effectively change the rotation of
the arrow by resizing so that the relative corners change.

For example, you can turn a bottom left to top right arrow into a bottom
right to top left arrow by dragging the top-right corner anchor to the left,
effectively turning the anchor into the top-left corner anchor. Do you know
what I mean?

Anyway, all I am sending for resizes is the end rectangle, and that no
longer has enough information in it to indicate that such a transformation
took place.

Is there any information - a before and after transformation matrix or
something like that - that I can use instead to send more complete
information on what happened?

Thanks,

Doug